The emergence of new COVID-19 variants is seen denting the efficacy of vaccines and AstraZeneca is the first to take a hit.
The vaccine developed by the University of Oxford ran into trouble in South Africa on Sunday after it failed to ward off the B.1.351 variant in 95 percent of 1750 healthy and mostly young participants in a trial.
It had only 22 percent efficacy against mild and moderate illness, according to lead researcher Shabir Madhi, forcing the suspension of the planned roll-out of one million doses.
Health ministries have been worried especially in countries where the variant has been confirmed and less-wealthy countries relying on millions of Astra through the COVAX facility.
COVAX, the global program pursuing equitable access to vaccines, has allocated 16 million doses of Astra to Nigeria. Outside COVAX, Nigeria expects to receive 41 million Astra vaccine doses from the African Union, and a million doses from private sector donor, BUA Group.
A cause to worry?
It is not clear yet, if Nigeria will equally run into the same problem with AstraZeneca, although the developer has launched a new study to arm its vaccine sufficiently against the disturbing variant.
Nigeria has not yet found the South African variant and will continue with plans to distribute the AstraZeneca vaccine, Faisal Shuaib, director of the National Primary Healthcare Development Agency said in a monitored report.
He said sequencing of samples were still going on to detect the strain and subject samples from travellers returning from the United Kingdom and South Africa to further genomic sequencing.
Nigeria is also looking up to other sources of vaccines including 7.6 million doses expected from Pfizer-BioNTech and 18.4 million from Johnson & Johnson. Other sources are Russia and India, Shuaibu noted.
“AstraZeneca is not the only vaccine we have access to,” he said. “We do have options in case the South African variant is found in Nigeria.”
However, epidemiologists and virologists have urged that Nigeria keeps an eye on the developments on deployment of AstraZeneca in other countries.
Although disappointed that Nigeria is struggling to develop its own vaccine, relying heavily on donations, Oyewale Tomori, a professor of virology said the National Agency for Food and Drug Administration (NAFDAC) must gear up for evaluation of the vaccine’s fitting for local use and monitor other vaccines as well.
“What should we do? Monitor what is happening in countries where the AstraZeneca vaccine is being used and decide based on what information we gather. We should get our NAFDAC to evaluate other vaccines like the Johnson & Johnson and see how that also works. As to subjecting the vaccines to test here, how are you going to test without the facilities for doing clinical trials?” Tomori, former vice-chancellor of Redeemers University told BusinessDay.
Variants other than South Africa’s
Nigeria has another local variant in the offing that it is yet to understand its influence on the infection rates in the country.
Chikwe Ihekweazu, the director-general of the Nigeria Centre for Disease Control (NCDC), last month, said there is no evidence yet to show that the new variant of coronavirus in Nigeria, P681H, is associated with the second wave of infections.
The variant detected in August and October, before Nigeria slipped into a second wave of the pandemic, shares one mutation with the B1.1.7 UK variant, but differs from the 22 other lineage defining mutations in the UK variant, the DG explained during a webinar, convened by the World Health Organisation (WHO).
Besides that, 18 lineages have been detected in Nigeria since the pandemic, but capacity genomic surveillance to analyse the variants and properly understand the pandemic.
If the ongoing NCDC study eventually finds variance associated with changes in transmission in the local variant, UK or South African variant, there might be a need for serious adjustment to vaccination.
But in the interim, Nigeria can go ahead with the AstraZeneca, given the proven efficacy of about 90 percent, fridge stability quality and heaper pricing of less than $4, said a scientist who didn’t want to be named.
“If there are no serious problems stemming from AstraZeneca, we should just use local administration here as clinical trials. We have nothing to lose. Setting up a separate clinical trial for the vaccine could be an expensive venture,” the scientist explained.